Techniques for efficiently executing a plurality of virtual machines on a plurality of servers have been proposed. For example, a virtual machine management server reads measured data indicating performance of each of the virtual machines in each of predetermined time periods, data on storage capacities of the servers allowing the virtual machines to run thereon, and data on storage capacities of the virtual machines from a database (DB). The virtual machine management server calculates, on the basis of the read data, performance of each of the virtual machines in each of the predetermined time periods when run on each of the servers. The virtual machine management server determines a combination of the virtual machines and the servers which provides the maximum sum of values indicating performance of the virtual machines in each of the predetermined time periods. The virtual machine management server stores an image file (also referred to as an image) of each of the virtual machines in a storage region of the server corresponding to the each of the virtual machines to redeploy the virtual machines in accordance with the determined combination.
Japanese Laid-open Patent Publication No. 2005-115653 discloses a related technique.